Compress video online
Reduce the size of MP4, WebM, MOV, and other videos directly in the browser. Adjust quality, resolution, FPS, and audio, process multiple files in sequence, and download the result.
Files are not uploaded to a server. Compression runs in your browser.
How to compress video online
- Step 1
Add videos
Choose files or drag them into the workspace.
- Step 2
Choose a preset
Balanced mode works for most videos; settings can be adjusted manually.
- Step 3
Start compression
FFmpeg runs in the background while the queue and overall progress stay visible.
- Step 4
Download the result
Compare sizes and download files individually or as a small ZIP archive.
Supported formats
Source formats: MP4, WebM, MOV, M4V, MKV, and AVI. The main output format is MP4 with H.264; WebM with VP9 is available as an additional option. Some rare codecs inside a container may not be supported by the browser FFmpeg build.
Browser processing limits
Files up to 100 MB start without a warning. 100–500 MB files require more time, and after 500 MB the risk of running out of memory increases. Files from 1 GB are blocked. Speed depends on duration, resolution, CPU, and available device memory.
Frequently asked questions
Is the video uploaded to a server?
No. Video is processed locally on your device. Packlet loads only the compression engine into the browser; file contents and names are not sent to a server.
Which video formats are supported?
You can add MP4, WebM, MOV, M4V, MKV, and AVI. The result is saved as compatible MP4 or optional WebM. Support for a specific source codec depends on FFmpeg.
Why does compression take a long time?
Video transcoding requires a lot of computation. The first run also includes loading the WebAssembly engine. Long videos, high resolution, and slower devices increase processing time.
Why did the compressed file become larger?
The source file may already be well optimized. By default, Packlet marks such a result as not useful and suggests stronger compression, lower resolution, or audio removal.
Can I compress several videos at once?
Yes. Add multiple files — they are processed sequentially to avoid overloading device memory. An error in one video does not stop the rest of the queue.
Can I remove audio from a video?
Yes. Choose the “Remove audio” audio mode or the “No audio” preset before starting compression.
Why did a large video fail to process?
The browser is limited by available memory. Files from 100 MB show a warning, files over 500 MB have a high risk, and files of 1 GB or more are blocked. Close extra tabs or use a smaller source file.